The GNU Mach Reference Manual documents the architecture, the usage and the
programming of the GNU Mach microkernel. At the moment, the manual documents
the interface completely, but is not very useful as a tutorial or introduction
into the Mach architecture.

Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no Invariant
Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
is included in the section entitled
GNU Free Documentation License.